Essay on The Evolution of Reptiles

“We often think of the T-Rex as this huge crocodile-like bipedal reptile but in fact, its closest modern relative are birds and the T-Rex was actually the dinosaur equivalent of a chicken” explains Linda Rushmore, head researcher at the North Carolina Museum of Natural Sciences’ Paleontology

Adaptive radiation of different organisms have occurred throughout geological time through the filling of ecological niches. Organisms different from one another are capable of radiating greatly, as they evolve traits that allow them to thrive better in their environment. The Anolis lizards of the Caribbean islands are a great example of a single genus to have radiated not once, but multiple times through very similar mechanisms. Different populations of the Anolis phenotypically vary in their morphological traits to facilitate adaptation to particular niches. These phenotypic variations have evolved in convergence in more than one occasion, as recently discovered fossil specimens show similar patterns in morphology to modern Anolis.

Birds are closely related to crocodiles because they share the same ancestry with the dinosaurs. To compare the crocodile and lizard, one would think the lizard is closely related to crocodiles, as we read in our text, "similar structures don't always reveal common ancestry." Crocodiles and birds evolved having the same common ancestry as the dinosaur. Lizards, on the other hand, do not share a close common ancestor with crocodiles or dinosaurs, their common ancestry is more distant.

A part of the origin is how they came to became to be humans. They began interbreed with humans when they came to earth, and this began to make a new breed that could allow them to change forms. Toptenz.net says, “They altered our DNA so we don’t use our brain to its full capacity, putting a limit on our consciousness, and making us easier to control. As evidence, Icke points to the fact that we have reptile genes within our brain. In fact, the Reptilian brain is the oldest of the three parts that control the brain.”

The top theory as of now among scientists is that pterosaurs, crocodiles, and dinosaurs are closely related to each other as a group. In the kingdom of Animalia, these three belong to a group known as archosaurs.

Turtles have been on this earth for more than 200 million years. They evolved before mammals, birds, crocodiles, snakes and even lizards. The earliest turtles had teeth and could not retract their heads, but other than this, modern turtles are very similar to their ancestors. Several species of turtle can live to be over a hundred years old, including the American Box Turtle.

No, lizards that are similar according to body type are not more closely related based on the results obtained from the DNA sequence analysis. The reason for this is because their body

The main reason I listed was their hearing, which for a small lizard is rather advanced. Many geckos have a large vocal range, capable from being heard across the jungles they’re native to. Most geckos also have the ability to understand and respond to other geckos calls

They have a bony endoskeleton with a backbone but no jaws, they have hollow bones and four limbs.

al. 2004, (Agosta et. al. 2004) critique the article by stating that there was not sufficient information that was provided for the evidence to claim that the horned lizards were adapting. The points Agosta et. al. 2004 thought that Young et. al. addressed was “evidence that selection has occurred on the trait in question” (Young et. al. 2004). An example of this would be when Young et. al. talked about how the horned lizards with the shorter length were least favored by selection therefore lizards with longer horns would have greater fitness (Young et. al. 2004). On the other hand, according to Agosta et. al. claim that Young et. al. failed to present three major points. The three major points are the “existence of a functional explanation for putative fitness differences associated with the trait”, “evidence for heritability of phenotype differences corresponding to trait variation”, and “knowledge of phylogeny such that putative adaptations can be shown to have originated in selective regimes in which they are currently advantageous” (Agosta et. al. 2004). Agosta et. al. thought the young et. al. lacked the information to support whether the horned lizards had adapted to the shrikes (Agosta et. al.

Mesozoic vertebrates of Texas have received less attention than Paleozoic. In the early 1900s E. C. Case collected and reported amphibians and reptiles found in Triassic sediments along the eastern edge of the High Plains, and Sankar Chatterjee of Texas Tech University has also made important discoveries there. Notable are skeletons of phytosaurs. These aquatic reptiles, up to thirty feet in length, had elongated snouts armed with thick, sharply pointed teeth. Their habits were probably much like those of modern crocodiles. Some lightly armored forms were not unlike crocodiles in appearance, except for their long, hook-nosed snouts, but some armored types of phytosaurs may have looked almost like arthropods. Through work centered at the University of Texas at Austin, parts of the Trans-Pecos region have yielded important fossils of Cretaceous reptiles, among them enormous crocodiles and the largest known pterosaur. Much of Central Texas probably contains bones of Cretaceous vertebrates, but the land is so heavily vegetated that discoveries are few. However, remains of dinosaurs, plesiosaurs, and even primitive mammals have been found and are preserved at the University of Texas and Southern Methodist University. Fossil vertebrates, especially mammals, of the middle to late Tertiary and Pleistocene ages abound in Texas. Much of the fossil history of horses, camels, rhinoceroses, and other kinds of both living and

The article focuses on the description and biology of the Pygmy Short-horned Lizard, and why they differ from an ordinary lizard. The Pygmy Short-horned Lizard is the smallest of the horned lizards and it hardly exceeds 6 cm from snout to tail. Compared to other armoured horned lizards, the Pygmy Short-horned Lizard has relatively small horns on its head and body. The colour and pattern vary within the species; however, the colour typically blends with its environment, making it extremely difficult to detect when it is motionless. This is a type of protection it uses to protect from its preys. The tail of the Pygmy Short-horned Lizard is short and is incapable of regrowth if lost, unlike the tails of many other lizards. Also unlike some other lizards that lay eggs, the Pygmy Short-horned Lizard is viviparous. This means it gives birth to fully developed live young, and the newborns resemble adult lizards that are smaller and not fully developed horns (Hong 2009). Question: What are possible explanations for the eradication of the Pygmy Short-horned Lizard in Canada?

Lizards are a unique animal for various reasons, but I find one of these unique qualities to be especially fascinating. That is the respiratory system and the reptile’s spontaneous ventilation rate is directly related to temperature and partial pressure of oxygen (PO2). Whereas the mammals respiration is strictly related and driven by carbon dioxide (PCO2). In veterinary medicine this is something that comes up when it comes time to use anesthesia on a reptile for a surgical or other procedure in which they will need to be anesthetized. Inhalants are somewhat of a contradiction as the lizard can hold its breath for long periods of time during the induction phase of inhalant anesthesia,

Frilled lizards are found in the tropical and woodland forests of Australia. They are known for their long tail and large neck that expands when they feel threated. Now even though they are very cool they are like most lizards and eat whatever they can find. So it makes them an omnivore. Their main prey is insects, spiders, and rodents. Their skin is made of scales and if you ever get to touch one it will feel like little bumps of small rocks. Luckily for these little guys they probably won’t get touched a lot. They are not on the conservation list and they aren’t in a lot of zoos.

Alligators and crocodiles have been around for a number of years. They are part of history and also a part of the dinosaur family. Growing up I was always curious of how an alligator and a crocodile varied. If you have ever been curious of the difference between the two you are in luck, I have the answers.